1. Field of the Invention
The present invention relates to an improved insulated shipping container; with all or substantially all of the component parts of this container suitable for recycling (or which are biodegradable or can be composted). Thus, a shipping container according to this invention may be considered environmentally friendly, or “green.” More particularly, this invention relates to an insulated shipping container having provision for preventing migration or stratification of particulate insulating material and thus preventing development of “hot spots” where ambient heat could reach the contents being shipped were the particulate insulation allowed to shift during shipping.
In order to protect item(s) being shipped, the present container is especially configured and constructed to provide both shock absorption, to provide temperature regulation through the use of a combination of particulate insulation (i.e., insulation pellets) and a temperature control material, such as refrigerated gel packs or dry ice. Also, the present container is configured to prevent voids or gaps from forming in the particulate insulation material, which gaps would lead to localized “hot spots” and could result in damage to or degradation of temperature sensitive cargo during transit.
2. Related Technology
Traditionally, containers for shipping temperature sensitive products have generally included conventional cardboard shipping containers having an insulating material therein. The insulating material may be simple loose-fill Styrofoam “peanuts,” for example, in which a chunk of dry ice is placed along with the material to be shipped. Another variety of conventional insulated shipping container utilized panels or containers made of an insulating material, such as expanded polystyrene (EPS). EPS is a relatively inexpensive insulating material, and it may be easily formed into a desired shape, has acceptable thermal insulating properties for many shipping needs, and may be encapsulated or faced with protective Materials, such as plastic film or metal foil, or plastic film/metal foil laminates.
Containers including EPS are often provided in a modular form. Individual panels of EPS insulation, possibly wrapped in foil or the like, are preformed using conventional methods, typically with beveled, mitered, or square (i.e., 90°) edges. The panels are then inserted into a conventional cardboard box type of shipping container, one panel against the floor wall, and against each side wall, to create an insulated cavity within the container. In this arrangement, the beveled edges of adjacent panels form seams at the corners of the container. A product is placed in the cavity and a plug, such as a thick polyether or polyester foam pad, is placed over the top of the product before the container is closed and prepared for shipping. In many cases, a coolant, such as packaged ice, gel packs, or loose dry ice, is placed around the product in the cavity to refrigerate the product during shipping.
Alternatively, an insulated body may be injection molded from expanded polystyrene, forming a cavity therein and having an open top to access the cavity. A product is placed in the cavity, typically along with coolant, and a cover is placed over the open end, such as the foam plug described above or a cover formed from EPS.
For shipping particularly sensitive products, such as certain medical or pharmaceutical products, expanded rigid polyurethane containers are often used, as expanded polyurethane has thermal properties generally superior to EPS. Typically, a cardboard container is provided having a box liner therein, defining a desired insulation space between the liner and the container. Polyurethane foam is injected into the insulation space, substantially filling the space and generally adhering to the container and the liner. The interior of the box liner provides a cavity into which a product and coolant may be placed. A foam plug may be placed over the product, or a lid may be formed from expanded polyurethane, typically having a flat or possibly an inverted top-hat shape.
With all of the conventional shipping containers outlined above, many of the component parts of the container are not biodegradable, and recycling of the materials of the container is also problematic. Some countries, particularly the European countries, impose a tariff or tax on products that do not meet recycling guidelines. Many conventional insulated shipping containers do not meet these recycling guidelines, so that the costs of using such non-compliant containers is increased by the applied additional taxes. Particularly, insulated shipping containers of the type utilizing polyurethane foam injected into a space between an inner and an outer nested cardboard boxes create a particularly difficult disposal problem. When polyurethane is injected into such a container, it generally adheres substantially to the walls of both the inner and the outer cardboard box. Thus, the cardboard and insulation components may have to be disposed of together, entirely preventing recycling of the container.
Accordingly, there is a need for an improved insulated shipping container which is “green” with substantially all of the components of the container being either biodegradable, or recyclable, or both.